Abstract

Picture a silica tube no thicker than a human hair, and then picture a fluid sample in that tube--a sample so small that the tiniest drop of water seems like a flood in comparison to it. Now imagine zapping the tube with electricity, shining a little ultraviolet or visible light on the migrating particles in the sample, and you have the basics for capillary electrophoresis, an analytical technique that holds great promise for investigators in the life sciences. Robert Palmieri, principal research chemist at Beckman Instruments Inc. in Palo Alto, Calif., says capillary electrophoresis, a method refined in the past decade, is a valuable tool for researchers. "It gives different information about the material you're working with in addition to the information you get from HPLC [high-performance liquid chromatography], and ion exchange and gel electrophoresis," he says. Pharmacologists, molecular biologists, biochemists, and other scientists have used capillary electrophoresis during the last few years to analyze new pharmaceuticals for purity and to separate and detect amino acids, proteins, and oligonucleotides. Scientists have also examined the usefulness of this analytical method in a clinical setting. Possible clinical applications are the analysis of therapeutic doses of administered drugs and the fractionation